Today one in five Germans have an immigrant background.

The number of people with an immigrant background in Germany rose 8.5 percent to a record 18.6 million in 2016, largely due to an increase in refugees, the Federal Statistics Office said on Tuesday.

Just over a fifth of the population – 22.5 percent – were first or second generation immigrants with at least one parent born without German citizenship, the office said.

The figures come in the build-up to national elections in September, with Chancellor Angela Merkel’s Social Democrat challenger warning against a repeat of 2015 when she opened the borders to hundreds of thousands of migrants.

Around 2.3 million people in Germany have family links to the Middle East, a rise of almost 51 percent since 2011, and around 740,000 people have African origins, an increase of 46 percent since 2011, the figures showed.